<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <input id="file" type="file" />
  <script>
    file.onchange = function(){
      console.dir(this.files[0])//二进制文件
      var reader = new FileReader()
      reader.onload = function(evt){
        console.log(evt)
      }
      reader.readAsArrayBuffer(this.files[0])
    }
  </script>
</body>
</html>
